stuperbad/LED-WatchA round LED wristwatch: 132 small LEDs (12 hours, 60 minutes, 60 seconds as three concentric rings) driven straight from an AVR microcontroller, with an accelerometer to wake it.
Front mcu db64 is an open-source printed circuit board by stuperbad, from the stuperbad/LED-Watch repository on GitHub. It is a 4-layer board of 44 × 51.1 mm with 218 parts on 40 nets.
It is built around the AVR128DB64-I/MR, DMP21D0UFB4-P and LIS2DW12, with the PKMCS0909E4000-R1 among its other parts. Its parts include 24 transistors, 9 resistors, 7 capacitors, 3 connectors and 2 switches.
A round LED wristwatch: 132 small LEDs (12 hours, 60 minutes, 60 seconds as three concentric rings) driven straight from an AVR microcontroller, with an accelerometer to wake it. Two variants share the idea and some code but have different hardware, so each lives in its own folder.
| Open this KiCad project | Variant | Status |
|---|---|---|
single-color/hardware/LED Watch - Single Color.kicad_pro | White LEDs, solar-charged (TI BQ25570 + one Anysolar cell + two small LiPo cells), AVR128DB48, piezo buzzer, 42 mm board | Revision A is an order candidate (JLCPCB quote $308.63 for 5 assembled boards), fully routed, DRC clean, not ordered yet. Firmware (alarm, weekday lights, sounds) and a browser simulator are in the folder. Start with single-color/README.md. Tagged rev-A. |
rgb/LED Watch - RGB.kicad_pro | RGB LEDs that JLCPCB can assemble (common-anode), AVR128DB64, solar + LiPo + buzzer like the single-colour watch | Placement sketch only (2026-10-15): board size and fit worked out, no schematic or routing yet. Start with rgb/docs/DESIGN-SKETCH.md. The earlier RGB board (Harvatek LEDs, ATmega165PA, fully routed, not buildable: parts out of stock) is in rgb/archive/2026-10-14 old RGB board ... |
LED-Watch/
single-color/ the solar white-LED watch
hardware/ KiCad project, custom footprints, production files (Gerbers, BOM, placement), schematic generator
firmware/ AVR firmware (C), browser simulator, tests
docs/ design notes, decision log, checklists, datasheets, research
tools/ layout / routing / checking scripts
archive/ older board generations of this variant
rgb/ the RGB watch
LED Watch - RGB.* the RGB project (placement sketch, 2026-10-15)
docs/ DESIGN-SKETCH.md, pin plan, BOM candidates
footprints/ data/ tools/ renders/ LED footprint, LED map, sketch generator, pictures
mechanical/ outline drawings and the 3D print (of the old 43 mm board)
archive/ the old routed RGB board and everything olderBoth variants live side by side on main; branches are for work in progress. Revisions are git tags (rev-A, ...) rather than file names.
Code that both variants will share (LED matrix scan, RTC and mode state machine, accelerometer driver) can move to a top-level shared/ folder when RGB firmware starts; single-color/firmware/ is the starting point.
Open single-color/README.md (what everything is), then single-color/docs/REVIEW-GUIDE.md (what to check first), and single-color/docs/PRE-ORDER-CHECKLIST.md (what is still open).
| Qty | Value | Footprint | References |
|---|---|---|---|
| 139 | NCD0808RGB1 / MHPA0808RGBDT | RGB0808_CommonAnode | IND1, IND2, IND3, IND4, IND5, IND6, IND7, U10, U100, U101, U102, U103, U104, U105, U106, U107 +123 |
| 24 | DMP21D0UFB4 | Diodes_DFN1006-3 | Q1, Q2, Q10, Q11, Q12, Q13, Q14, Q15, Q16, Q17, Q18, Q19, Q20, Q21, Q22, Q23 +8 |
| 18 | R | R_0402_1005Metric | RC1, RC2, RC3, RC4, RC5, RC6, RC7, RC10, RC11, RC12, RC13, RC14, RC15, RC16, RC17, RC18 +2 |
| 7 | 100n | C_0402_1005Metric | CM1, CM2, CM3, CM4, CM5, CM6, CM7 |
| 3 | 6.49M | R_0402_1005Metric | R50, R53, R55 |
| 2 | 10k | R_0402_1005Metric | R20, R21 |
| 2 | 10n | C_0402_1005Metric | C51, C53 |
| 2 | 18p | C_0402_1005Metric | C20, C21 |
| 2 | 3.74M | R_0402_1005Metric | R54, R56 |
| 2 | 4u7 | C_0402_1005Metric | C50, C52 |
| 2 | LiPo | JST_SH_SM02B-SRSS-TB_1x02-1MP_P1.00mm_Horizontal | J1, J1B |
| 2 | SW | SW_Push_1P1T_NO_CK_KMR2 | SW1, SW2 |
| 2 | cell pad | KXOB25_cell_pad_2.5x7.4mm | SC1-, SC1+ |
| 1 | 1.47M | R_0402_1005Metric | R52 |
| 1 | 10uH | L_1210_3225Metric | L2 |
| 1 | 22u | C_0805_2012Metric | C54 |
| 1 | 22uH | L_1210_3225Metric | L1 |
| 1 | 32.768kHz | Crystal_SMD_3215-2Pin_3.2x1.5mm | Y1 |
| 1 | 5.11M | R_0402_1005Metric | R51 |
| 1 | AVR128DB64-I/MR | VQFN-64-1EP_9x9mm_P0.5mm_EP5.4x5.4mm | MCU |
| 1 | BQ25570 | BQ25570RGR_VQFN-20_3.5x3.5mm_P0.5mm_EP2.05mm | BQ |
| 1 | LIS2DW12 | LGA-12_2x2mm_P0.5mm | IMU |
| 1 | PKMCS0909E4000-R1 | Piezo_Murata_PKMCS0909E4000-R1_9x9mm | BZ1 |
| 1 | UPDI pogo | UPDI_Pogo_1x4_P1.27mm_2Guide | J2 |
.kicad_pcb.jpg?size=s&soon)
stuperbad/LED-Watch
A round LED wristwatch: 132 small LEDs (12 hours, 60 minutes, 60 seconds as three concentric rings) driven straight from an AVR microcontroller, with an accelerometer to wake it.
stuperbad/LED-Watch
A round LED wristwatch: 132 small LEDs (12 hours, 60 minutes, 60 seconds as three concentric rings) driven straight from an AVR microcontroller, with an accelerometer to wake it.
stuperbad/LED-Watch
A round LED wristwatch: 132 small LEDs (12 hours, 60 minutes, 60 seconds as three concentric rings) driven straight from an AVR microcontroller, with an accelerometer to wake it.
stuperbad/LED-Watch
A round LED wristwatch: 132 small LEDs (12 hours, 60 minutes, 60 seconds as three concentric rings) driven straight from an AVR microcontroller, with an accelerometer to wake it.
.kicad_pcb.jpg?size=s&soon)
stuperbad/LED-Watch
A round LED wristwatch: 132 small LEDs (12 hours, 60 minutes, 60 seconds as three concentric rings) driven straight from an AVR microcontroller, with an accelerometer to wake it.
stuperbad/LED-Watch
A round LED wristwatch: 132 small LEDs (12 hours, 60 minutes, 60 seconds as three concentric rings) driven straight from an AVR microcontroller, with an accelerometer to wake it.
stuperbad/LED-Watch
A round LED wristwatch: 132 small LEDs (12 hours, 60 minutes, 60 seconds as three concentric rings) driven straight from an AVR microcontroller, with an accelerometer to wake it.
/2025-11-19%20RGB%20empty%20version%20(unrouted%20board%20%2B%20schematic).kicad_pcb.jpg?size=s&soon)
stuperbad/LED-Watch
A round LED wristwatch: 132 small LEDs (12 hours, 60 minutes, 60 seconds as three concentric rings) driven straight from an AVR microcontroller, with an accelerometer to wake it.
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It measures 44 × 51.1 mm and has 4 copper layers, 1.6 mm thick.
218 parts, built around the AVR128DB64-I/MR, DMP21D0UFB4-P, LIS2DW12 and PKMCS0909E4000-R1. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
From the stuperbad/LED-Watch repository on GitHub, at the commit this page was made from: the board is rgb/variants/front-mcu-db64.kicad_pcb. PCBKit opens the board in the browser, with nothing to install.
Its repository states no licence, so its author keeps all rights: ask stuperbad before reusing the design.